USF1 and neoplasm: This results in p53 stabilization and transient cell cycle arrest.225,226 In about half of GC patients, USF1 expression is lower in tumor tissue than non-tumor tissue, and 88% of patients with low USF1 expression have H. pylori infection.227 Low expression of p53 closely correlates to low expression of USF1, and low expression of both is associated with poor prognosis.227